As conventional PDP drive control of a PDP apparatus, in the operation of a reset period of a sub field (abbreviated as SF) of a field (field period), waveforms (reset pulses) for writing and adjusting charges for the cells are applied to display electrodes, thereby generating minute discharges (reset discharges) in the cells. By this means, the generation of discharges (address discharges) in selected cells in a next address period is ensured. In the basic drive control (normal drive: referred to as first drive), reset pulses are applied without thinning in the operation of the reset period of a SF.
As a PDP drive method, based on the above-described first drive, the following reset thinning drive (referred to as second drive) exists conventionally. In the second drive, application of the reset pulses is thinned in the operation of the reset period of a high-luminance SF that satisfies predetermined conditions, thereby realizing high-contrast control. In the second drive, in accordance with the load ratio of display in units of SF (SF load ratio or SF display ratio), reset operations are thinned out from the high-luminance SF side when the SF load ratio is zero. Also, when the SF load ratio is not zero, thinning of the reset operations of the SF is not carried out (first drive is employed). As described above, by virtue of the control of the second drive, in other words, by the control of the switching between the first drive and the second drive, the background luminance is reduced in correspondence with the amount of reduction in generation of the reset discharges by the reset thinning in the second drive, and the high-contrast display is achieved.
The SF load ratio is the ratio of the cells which are lit (on) with respect to all the cells of a SF. The SF load ratio is zero when there is no cell to be lit in the SF. The SF load ratio is not zero when there are cells to be lit in the SF. Also, the above-described high-luminance SF is one or more SFs in which weighting for luminance in a field is high. The SF in which the control of the second drive is to be employed (SF in which reset thinning can be selectively executed) is one or more continuous high-luminance SFs in accordance with the arrangement of SFs in a field.
Hereinafter, the state where the second drive is executed or effective is referred to as “ON” or the like. The state where the second drive is not executed or ineffective, in other words, the state where the first drive is executed is referred to as “OFF” or the like. Also, since the “ON” state corresponds to the state where the reset pulse is not applied, it is also expressed as “Roff” (reset off). Since the “OFF” state corresponds to the state where the reset pulse is applied, it is also expressed as “Ron” (reset on). Further, the operation (execution) of transition/switching of the drive state in the control of the second drive from “OFF” to “ON” is expressed as, for example, “OFF→ON”, and the operation (cancel) of transition/switching from “ON” to “OFF” is expressed as, for example, “ON→OFF”.